X-ray microscope is known, which allows to obtain image of internal structure of objects. The operation of such microscope is based on principle of shadow projection of the object in divergent X-ray beam emitted by a point source (Encyclopedia “Electronica”, Moscow, “Sovetskaya Entsiklopediya” publishing house, 1991, p.478) [1]. This microscope has been called shadow, or projection, microscope. The projection microscope comprise usually a microfocus X-ray tube, a chamber for placement of the studied object, and recording means. Resolution of projection X-ray microscope is the greater, the smaller size of radiation source and its distance from the object. The utilization is known, in particular, in such microscopes of the tubes with focal spot of 0.1 to 1 μm in diameter [1]. To further reduce the effective size of the source, diaphragming is used (Physical Encyclopedia, Moscow, “Sovetskaya Entsiklopediya” publishing house, 1984, p.639) [2].
However, with decreasing source size or with its diaphragming, its intensity becomes insufficient to ensure acceptable contrast ratio of the enlarged image. Overcoming of this drawback requires substantial increase in exposure time. Increase of the source size for enhancement of its effective intensity results in blurring of the image obtained and decrease in resolution.
With creation of X-ray capillary optics of total external reflection, the possibility has arisen of utilization in X-ray microscopes of extended (comparable to the object studied) X-ray sources. In such microscopes, chamber with the object studied is placed between extended X-ray source and entrance end face of X-ray lens with channels diverging towards image recording means (international application PCT/RU 94/00189, international publication WO 96/01991, 25.01.96 [3]). Specifically, said reference discloses use of conical X-ray lenses and bell-type lenses, the latter ones being noted as more efficient. Increase in the source size has no effect on resolution of these microscopes, since it corresponds to the size of the object's fragment brought into field of vision of separate channel of X-ray capillary lens. The X-ray microscope of said design is the most close to the one proposed.
However, with decrease in diameter of the separate channels down to the level reached in the state-of-the-art technologies in monolithic and, in particular, in integral lenses (U.S. Pat. No. 6,271,534, publ. 07.08.2001 [4]), entrance size of the separate channel in X-ray lens ceases to be a determining factor. This is accounted for by the fact of size Δ of the field of vision of lens' separate channel mentioned being of the orderΔ=d+2Lθc,  (1)                where d denotes entrance diameter of separate channel,                    L is a distance between the object studied and entrance of the X-ray lens channel, and            θc is critical angle of total external reflection of the channels walls material.                        
With small diameters d and low radiation energies used, in particular, in studies of biological objects, when angle θc may reach 10−2 radian, second term in the expression (1) above becomes dominant. Thus, for example, for L=1 mm and d=0,1 micron we obtain:d=0,1 micron=10−7 m<<2·10−5 m=2·1·10−3 m·10−2=2Lθc.Consequently, developments in manufacturing technology of X-ray lenses don't allow to enhance precision characteristics of X-ray microscopes of known design utilizing extended sources.